Author:

Millay,M.A.;Taylor,T.N.

Year:

1980

Title:

An unusual Botryopterid sporangial aggregation from the Middle Pennsylvanian of North America.

Reference:

Millay,M.A. et al. (1980) An unusual Botryopterid sporangial aggregation from the Middle Pennsylvanian of North America. American Journal of Botany Vol. 67 # 5 P. 758- 773

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